Patent GB-756910-A (GB)
Title: Folding umbrella
IPC: A45B19/02
Filed: 1954-11-24
Abstract: 756,910. Foldable umbrellas. NUSSBAUMER, M. Nov. 24, 1954 [Nov. 25, 1953], No. 34026/54. Class 134. In a folding umbrella having a cover 1 preferably made of a thermoplastic material such as polyvinyl chloride or polyethylene with inflatable ribs 30, the stick 2 is an axially compressible metal tape volute forming a pump for inflating the ribs. The metal tape 4 which may be of stainless steel or an aluminium alloy is attached at one end to the handle 3 (Fig. 4) by screws 9 or sharp pins and is manufactured so that the volute assumes its greatest axial extension when the tape is unstressed. One of the lower windings of the tape has one or more holes 8. The handle 3 has one or more slits 12 and a locking ring 11 sliding on a conical external face 10. A hole 14 in the end of the handle leads to a cylindrical recess provided with an annular bead 13. The other end of the tape 4 is secured in a groove 7 in a cylinder 5 (Fig. 3) by screws 6 or sharp pins. A pin 19 supported by a bracket 18 screwed to the cylinder 5 projects into one of the air passages in the seating 16 of a valve 17 and is normally held by a spring 20 so that a pin 21 abuts part of the bracket 18. The umbrella cover 1 is formed by an upper foil 27 in the shape of a polygon and a lower foil 23 in the shape of a star which is welded to the upper foil to form the hollow ribs 30 which are of smaller section in their middle portion than at the ends and are reinforced internally by a central partition welded along the length of each rib. The lower foil 23 is welded along a seam 24 to a flange 22 on the cylinder 5, and the upper foil 27 is welded along a seam 29 to a disc 26 which is welded to the flange 22 at spots 25 which are subsequently perforated to provide openings 28. The handle 3, cylinder 5, and disc 26 are preferably made of the same material as the umbrella cover. The ribs are inflated by placing the hand over the hole 14 and compressing the stick 2 so that air is forced through the valve 17 and the slits formed between adjacent welding spots 25 into the space between the foils 23 and 27. The stick returns to its extended condition due to the stress in the metal tape and air enters through the hole 14 or through the hole 8 when the stick is fully extended. When pumping is complete the stick is stiffened in the extended condition by turning the handle 3 in the winding direction of the tape 4 and moving the locking ring 11 down the handle to compress the wall of the handle on to the lower turns of the tape. To deflate the ribs the locking ring 11 is moved up the handle and the stick compressed until the shoulder 15 moves the pin 19 upwards to open the valve 17 and allow the air to escape through the hole 14. The bead 13 of the handle 3 engages the end of the cylinder 5 and the handle is locked in this position by moving the locking ring 11 downwards. The deflated cover can then be folded around the collapsed handle, any air trapped inside the folded cover escaping through the holes 28. An additional foil may be welded to the disc 26 to prevent rain entering the holes 28, and the stability of the umbrella may be increased by means of a star-shaped foil having arms connected to the ribs 30 and a centre portion connected to a ring slidably mounted on the stick 2.